How can I search or sort a cell array of vectors when the vectors have non-uniform length?

Hello,

I've been trying to sort a 1xN cell array of vectors by the first element in the vector, where the vectors do not have the same length, without using a for loop. This problem can be reduced to being able to return the first element in the vector at each row of the cell array.

Specifically, I have an undirected graph where each each vector in a cell array has the node as the first element, and all of the nodes it is connected to in the elements after that.

Example: If Node 1 is connected to node 2 and 4, and Node 3 is connected to node 4, an unsorted cell array A representing this is: A = {[1,2,4];[3,4];[2,1];[4,1,3]}

I want to find some method of searching for the row of cell array A corresponding to node 2.

I've tried using the command sortrows([A{:}]), but having non-uniform vectors forces cell2mat to convert the cell array to a single row.

Also, I've tried A{:}(1) and A(1:4){1} to only return the first column in the cell array, but this causes a "Bad cell reference operation" error.

Would anyone happen to know of some easy way to do this without a for loop?

Thanks, Dennis

[per isakson]

"return the first element in the vector at each row of the cell array"

    >> cellfun( @(vec) vec(1), A )
    ans =
         1
         3
         2
         4

[Dennis Yeh]

Awesome, thank you!

Answer 1

[Dennis Yeh]

From per isakson's response, answer became

function output = sortCell(input, col)
data = cellfun( @(vec) vec(col), input);
data = [data,(1:length(data))'];
data = sortrows(data)
output = input(data(:,2));
end